Battery Description. Chevrolet PJJ 2000

For 1990-2009 cars

### General Description

The maintenance-free battery is standard equipment in all vehicles.

These vehicles may be equipped with more than one battery, depending on the powertrain used and optional equipment. The battery is completely sealed except for two small vent holes in the sides. These vent holes allow a small amount of gas produced in the battery to escape.

The battery has three functions in the electrical system:

1. The battery provides a source of energy for cranking the engine.
2. The battery acts as a voltage stabilizer for the electrical system.
3. The battery can, for a limited time, provide energy when the electrical load used exceeds the output of the generator.

The battery specification label contains information pertinent to servicing the battery. This information includes test ratings and original equipment. The label also includes numbers for recommended replacement parts.

### Battery Ratings

A battery has two ratings:

• | Reserve capacity

• | Cold cranking amperage

#### Reserve Capacity

The reserve capacity is an estimate of how long the vehicle can be driven with no generator output, the headlamps turned on, and a minimum electrical load (most of the accessories turned off). It is the maximum amount of time (in minutes) it will take for a fully charged battery, being discharged at a constant rate of 25 amperes and a constant temperature of 27°C (80°F), to reach a terminal voltage of 10.5 volts. Other temperatures or current draws, the state of charge, or the condition of the battery will affect how long the battery will actually last when the vehicle is being driven without generator output.

#### Cold Cranking Amperage

Cold cranking amperage is an indication of the ability of the battery to crank the engine at cold temperatures. This rating is the minimum amperage that the battery must maintain for 30 seconds at -18°C (0°F), while maintaining at least 7.2 volts. The actual performance of a battery will vary with actual temperature.

### Electrolyte Freezing

The freezing point of electrolyte depends on the specific gravity of the electrolyte, or state of charge. Since freezing may ruin a battery, protect the battery against freezing by keeping the battery charged. As long as the green dot shows in the built-in hydrometer, the battery will not freeze unless the temperature drops below -32°C (-25°F). A fully charged battery will not freeze unless the temperature drops below -54°C (-65°F).

### Protection During Vehicle Storage

Caution: Batteries produce explosive gases. Batteries contain corrosive acid. Batteries supply levels of electrical current high enough to cause burns. Therefore, in order to reduce the risk of personal injury while working near a battery, observe the following guidelines:

• | Always shield your eyes.

• | Avoid leaning over the battery whenever possible.

• | Do not expose the battery to open flames or sparks.

• | Do not allow battery acid to contact the eyes or the skin.

- | Flush any contacted areas with water immediately and thoroughly.

- | Get medical help.

Some electronic devices on the vehicle impose small continuous current drains on the battery. This is commonly called parasitic load. If the vehicle is not used for an extended time, these parasitic loads can discharge and eventually cause permanent damage to the battery. Discharged batteries can also freeze in cold weather. Refer to Electrolyte Freezing.

Do the following steps in order to help keep the battery in a charged state while storing the vehicle:

• | If the vehicle is likely to be stored over 30 days, check the built-in hydrometer and make sure the green dot is visible.

| Notice: Always turn the ignition OFF when connecting or disconnecting battery cables, battery chargers, or jumper cables. Failing to do so may damage the Powertrain Control Module (PCM) or other electronic components.

• | Disconnect the negative battery cable. This protects the battery from being discharged by parasitic current drains from the electrical system of the vehicle.

| Important: Any time the green dot in the built-in hydrometer of the battery is not visible, promptly recharge the battery.

• | If the battery cannot be disconnected, establish a regular schedule of recharging the batter every 20-45 days in order to maintain a high state of charge.

| Important: Original equipment maintenance-free batteries will not be damaged by charge rates of 50 amps or more, as long as the battery does not spew electrolyte from the vents or heat to over 52°C (125°F).

• | In order to keep the charging time low, use a battery charger that is capable of providing a charging voltage of at least 16 volts.

1. | Inspect the battery being charged every 45-60 minutes. Stop charging or reduce the charging rate as necessary.

2. | Stop charging within one hour after the green dot appears in the hydrometer in order to avoid overcharging.

| Important: A battery that remains in a discharged state for a long time may be difficult to recharge. The battery may also be permanently damaged.

• | Allow ample time for charging. Refer to Battery Charging .

When it is time to reconnect the battery, do the following steps:

1. Using a wire brush, lightly clean any oxidation from the contact face of the battery terminal before reconnecting the cable.

Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

2. Tighten the cable bolt.

Tighten

• | Tighten the cable bolt on a side terminal battery to 12 N·m (106 lb ft).

• | Tighten the cable bolt on top terminal battery to 18 N·m (13 lb ft).

3. Reset the clock, the push-button radio tuning, and other accessories before the vehicle is put back in service.

### Built-in Hydrometer

A built-in temperature compensation hydrometer is molded into the top of the maintenance free battery. When observing the hydrometer, make sure the battery top is clean. Use a light in poorly-lit areas.

Under normal operating conditions, one of three indications can be observed:

1. Any green appearance in the hydrometer is interpreted as a green dot . This means the battery is ready for testing.
2. A dark dot is visible. If the green dot is not visible and there is a complaint about cranking, refer to Charging System Check or Battery Electrical Drain/Parasitic Load .
3. A clear or light yellow dot means the electrolyte level is below the bottom of the hydrometer and is too low for diagnosis. The yellow dot may have been caused by the following conditions:

• | Excessive or prolonged charging

• | A broken case

• | Excessive tipping

4. When you find a battery in this condition, this may indicate high charging voltages caused by a faulty charging system. Because of this, the charging and electrical systems must be checked.
5. If the battery has a yellow or clear hydrometer, replace the battery if a cranking complaint exists.